CONTINUOUS METHOD AND DEVICE FOR PRODUCING INDUSTRIALLY RECYCLABLE PLASTER FROM INDUSTRIAL WASTE PLASTER

摘要

1. Continuous process for the obtaining of industrially usable gypsum from industrial waste gypsum by partial or complete hydrothermal conversion of waste gypsum to calcium sulphate alpha-hemihydrate in a tube reactor with the use of steam at temperatures of 130-180 degrees C., whereby hot steam is passed in co-current with the gypsum suspension into a vertically standing reactor tube and, by means of residence times of 3 to 20 min., the degree of reaction is controlled, characterised in that gypsum suspension and hot steam are introduced at the head of the reaction tube and the rate of flow amounts to 0.01-0.1 m/s, preferably 0.02-0.05 m/s and the suspension of the conversion product is withdrawn at the foot of the reaction tube.